U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Datums Page Page 1 of 7 Station ID: 8530095 PUBLICATION DATE: 06/16/2004 Name: ALPINE, HUDSON RIVER NJ NOAA Chart: 12343 Latitude: 40° 56.7' N ( 40.94500) USGS Quad: YONKERS Longitude: 73° 55.1' W ( -73.91830) To reach the tidal bench marks, proceed along the Palisades Interstate Parkway to Alpine, then continue to the west side of the Hudson River to Palisades State Park. The bench marks are located in the vicinity of the piers and buildings of the Palisades Interstate Park Commission. The tide gage and staff were at the Alpine Boat Basin. T I D A L B E N C H M A R K S
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 2 of 7 Station ID: 8530095 PUBLICATION DATE: 06/16/2004 Name: ALPINE, HUDSON RIVER NJ NOAA Chart: 12343 Latitude: 40° 56.7' N ( 40.94500) USGS Quad: YONKERS Longitude: 73° 55.1' W ( -73.91830) T I D A L B E N C H M A R K S PRIMARY BENCH MARK STAMPING: NO 1 1932 DESIGNATION: TIDAL 1 STA 1 MONUMENTATION: Tidal Station disk VM#: 2420 AGENCY: US Coast & Geodetic Survey (USC&GS) IDB PID#: KU1630 SETTING CLASSIFICATION: Rock cliff OPUS PID: LATITUDE: 40° 56.8' N ( 40.94670) LONGITUDE: 73° 55.1' W ( -73.91830) The primary bench mark is a disk set vertically into the east face of a rock cliff of the Palisades, 0.2 km (0.1 mi) north of the Alpine Yonkers ferry landing, 16.31 m (53.5 ft) SW of the SW corner of a small wood bridge, 9.75 m (32.0 ft) north of the NW corner of the Cornwallis Headquarters, 3 m (10 ft) west of the centerline of a gravel road on the west side of the house, and 1 m (2 ft) above road level.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 3 of 7 Station ID: 8530095 PUBLICATION DATE: 06/16/2004 Name: ALPINE, HUDSON RIVER NJ NOAA Chart: 12343 Latitude: 40° 56.7' N ( 40.94500) USGS Quad: YONKERS Longitude: 73° 55.1' W ( -73.91830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: NO 2 1932 DESIGNATION: TIDAL 2 STA 1 MONUMENTATION: Tidal Station disk VM#: 2421 AGENCY: US Coast & Geodetic Survey (USC&GS) IDB PID#: KU1631 SETTING CLASSIFICATION: Rock face of bluff OPUS PID: LATITUDE: 40° 56.8' N ( 40.94670) LONGITUDE: 73° 55.1' W ( -73.91830) The bench mark is a disk set vertically into the rock face of the Palisades, 0.2 km (0.1 mi) north of the Alpine Yonkers ferry landing, 35.66 m (117.0 ft) north of bench mark NO 1 1932, 16.76 m (55.0 ft) SW of the SW corner of a refreshment pavilion (north stand), 8.53 m (28.0 ft) west of the centerline of the employee's road, 5.33 m (17.5 ft) SW of the SW corner of the old Alpine Trail Monument, and 0.91 m (3.0 ft) above ground.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 4 of 7 Station ID: 8530095 PUBLICATION DATE: 06/16/2004 Name: ALPINE, HUDSON RIVER NJ NOAA Chart: 12343 Latitude: 40° 56.7' N ( 40.94500) USGS Quad: YONKERS Longitude: 73° 55.1' W ( -73.91830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: NO 3 1932 DESIGNATION: TIDAL 3 STA 1 MONUMENTATION: Tidal Station disk VM#: 2422 AGENCY: US Coast & Geodetic Survey (USC&GS) IDB PID#: KU1632 SETTING CLASSIFICATION: Retaining wall OPUS PID: LATITUDE: 40° 56.8' N ( 40.94670) LONGITUDE: 73° 55.1' W ( -73.91830) The bench mark is a disk set on top of and at the south end of a rock and concrete retaining wall, 0.2 km (0.1 mi) north of the Alpine Yonkers ferry landing, 32.31 m (106.0 ft) north of bench mark NO 2 1932, 30.48 m (100.0 ft) NW of a small pavilion, and 3 m (10 ft) east of the centerline of a trail. BENCH MARK STAMPING: 0095 A 1975 DESIGNATION: 853 0095 A TIDAL MONUMENTATION: Tidal Station disk VM#: 2423 AGENCY: National Ocean Survey (NOS) IDB PID#: SETTING CLASSIFICATION: Brick foundation OPUS PID: LATITUDE: 40° 56.7' N ( 40.94500) LONGITUDE: 73° 55.1' W ( -73.91830) The bench mark is a disk set vertically into the east face of a concrete and brick building, at the Alpine Boat Basin, east of exit 2 of the Palisades State Park, 35.94 m (117.9 ft) west of the chain link fence on the wood bulkhead at the Hudson River, 34.99 m (114.8 ft) north of the NE corner of a concrete garage building, 26.49 m (86.9 ft) from the SE corner, 4.66 m (15.3 ft) from the NE corner of the building, and 1 m (2 ft) above the pavement.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 5 of 7 Station ID: 8530095 PUBLICATION DATE: 06/16/2004 Name: ALPINE, HUDSON RIVER NJ NOAA Chart: 12343 Latitude: 40° 56.7' N ( 40.94500) USGS Quad: YONKERS Longitude: 73° 55.1' W ( -73.91830) T I D A L B E N C H M A R K S BENCH MARK STAMPING: 0095 B 1975 DESIGNATION: 853 0095 B TIDAL MONUMENTATION: Tidal Station disk VM#: 2424 AGENCY: National Ocean Survey (NOS) IDB PID#: SETTING CLASSIFICATION: Rock cliff OPUS PID: LATITUDE: 40° 56.7' N ( 40.94500) LONGITUDE: 73° 55.1' W ( -73.91830) The bench mark is a disk set vertically into the east face of the rock cliff of the Palisades, 0.2 km (0.1 mi) north of the Alpine Yonkers ferry landing, 45.26 m (148.5 ft) north of bench mark NO 3 1932, 26.64 m (87.4 ft) NW of a 3-foot high stone wall, 18.59 m (61.0 ft) north of the NE corner of a large stone pavilion building, 12.68 m (41.6 ft) SW of the SW corner of the first of several stone picnic tables along the shore, and 1 m (2 ft) above ground level.
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 6 of 7 Station ID: 8530095 PUBLICATION DATE: 06/16/2004 Name: ALPINE, HUDSON RIVER NJ NOAA Chart: 12343 Latitude: 40° 56.7' N ( 40.94500) USGS Quad: YONKERS Longitude: 73° 55.1' W ( -73.91830) T I D A L D A T U M S Tidal datums at ALPINE, HUDSON RIVER based on: LENGTH OF SERIES: 9 MONTHS TIME PERIOD: March 1976 - November 1976 TIDAL EPOCH: 1983-2001 CONTROL TIDE STATION: 8518750 THE BATTERY, NEW YORK HARBOR Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS: MEAN HIGHER HIGH WATER MHHW = 1.278 MEAN HIGH WATER MHW = 1.201 MEAN SEA LEVEL MSL = 0.658 North American Vertical Datum NAVD88 = 0.636 MEAN TIDE LEVEL MTL = 0.629 MEAN LOW WATER MLW = 0.058 MEAN LOWER LOW WATER MLLW = 0.000 North American Vertical Datum (NAVD88) Bench Mark Elevation Information In METERS above: Stamping or Designation MLLW MHW NO 1 1932 2.755 1.554 NO 2 1932 3.229 2.028 NO 3 1932 7.588 6.388 0095 A 1975 2.917 1.716 0095 B 1975 3.088 1.887
U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Ocean Service Page 7 of 7 Station ID: 8530095 PUBLICATION DATE: 06/16/2004 Name: ALPINE, HUDSON RIVER NJ NOAA Chart: 12343 Latitude: 40° 56.7' N ( 40.94500) USGS Quad: YONKERS Longitude: 73° 55.1' W ( -73.91830) D E F I N I T I O N S Mean Sea Level (MSL) is a tidal datum determined over a 19-year National Tidal Datum Epoch. It pertains to local mean sea level and should not be confused with the fixed datums of North American Vertical Datum of 1988 (NAVD88). NAVD88 is a fixed datum derived from a simultaneous, least squares, minimum constraint adjustment of Canadian/Mexican/United States leveling observations. Local mean sea level observed at Father Point/Rimouski, Canada was held fixed as the single initial constraint. NAVD88 replaces NGVD29 as the national standard geodetic reference for heights. Bench mark elevations relative to NAVD88 are available from NGS through the World Wide Web at National Geodetic Survey. NGVD29 is a fixed datum adopted as a national standard geodetic reference for heights but is now considered superseded. NGVD29 is sometimes referred to as Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological Survey Topographic Quads. NGVD29 was originally derived from a general adjustment of the first-order leveling networks of the U.S. and Canada after holding mean sea level observed at 26 long term tide stations as fixed. Numerous local and wide-spread adjustments have been made since establishment in 1929. Bench mark elevations relative to NGVD29 are available from the National Geodetic Survey (NGS) data base via the World Wide Web at National Geodetic Survey. NAVD88 and NGVD29 are fixed geodetic datums whose elevation relationships to local MSL and other tidal datums may not be consistent from one location to another. The Vertical Mark Number (VM#) and PID# shown on the bench mark sheet are unique identifiers for bench marks in the tidal and geodetic databases, respectively. Each bench mark in either database has a single, unique VM# and/or PID# assigned. Where both VM# and PID# are indicated, both tidal and geodetic elevations are available for the bench mark listed. The NGS's Integrated Data Base (IDB PID) provides geodetic datum based on traditionally leveled and bluebooked ties to the National Spatial Reference System(NSRS) https://www.ngs.noaa.gov/datasheets/. The NGS Online Positioning User Service (OPUS PID) provides geodetic datum based on GPS position & tie it to the NSRS https://www.ngs.noaa.gov/OPUS/. The NAVD88 elevation is shown on the Elevations of Tidal Datums Table Referred to MLLW only when two or more of the bench marks listed have NAVD88 elevations. The NAVD88 elevation relationship shown in the table is derived from an average of several bench mark elevations relative to tide station datum. As a result of this averaging, NAVD88 bench mark elevations computed indirectly from the tidal datums elevation table may differ slightly from NAVD88 elevations listed for each bench mark in the NGS database.